1. Technical Field
The following description relates to one or more techniques for managing management information.
2. Related Art
Conventionally, there is known as a communication technology employed for communication between a plurality of devices via a network an SSL (Secure Socket Layer) in which the communication is switched to encrypted communication by informing of a public key using an electronic certificate. In the communication technology, to attain high-security communication, an expiration date is generally set for the electronic certificate. The reason why an expiration date is thus set for the electronic certificate is that even though it is currently impossible to decrypt the encryption in the encrypted communication technology (or it takes long time to decrypt the encryption), there is a risk that the encryption is more likely to be decrypted as a same key (a secret key in the public key encryption) is used for a longer time. Hence, a date until which the encryption is presumed not to be easily decrypted is set as the expiration date.
Accordingly, security is not assured in communication using an expired electronic certificate. Therefore, in order to prevent the electronic certificate from being expired, there is proposed a technique in which a management device that manages the expiration date of the electronic certificate sends a warning mail for warning that the electronic certificate will expire soon to a destination that has previously been set a predetermined time period before the expiration date of the electronic certificate (for example, Japanese Patent Provisional Publication No. 2005-269558).
However, according to a technique described in Japanese Patent Provisional Publication No. 2005-269558, the management device is required to be always powered ON. Namely, when the management device is powered OFF, the management device cannot send the warning mail even at a moment when the warning mail is to be sent. For this reason, the conventional management device cannot adequately manage the expiration date of the electronic certificate.
Therefore, there is caused a problem that the communication security is not assured when a user performs the communication using the electronic certificate without knowing the electronic certificate has been expired.
Such a problem that the warning mail cannot be sent at a moment when the warning mail is to be sent as the management device is powered OFF does not apply only to the management of the expiration date of the electronic certificate but also to management of device information (for instance, information on toner empty in a printing device).